Regarding merging particles and body, its not realy possible.
But there is a trick that you can do in rendering that hides the polygon seems:
Use deffered rendering in general works good for this.
and if you dont do deffered rendering you could still make an extra render pass, with the region of intersection beeing colored as a mask.
Then you can use this masked area to make edge detection.
And at the edge, you can apply a blur.
So its a post processing method for hiding poly clippings.
Looks actually cool most of the time
@martontokes I think you should take a look at Grasshopper in Rhino. It’s a node-based programming environment like vvvv and is made for the kind of stuff you are after. Grasshopper has many plugins, which extend the functionality even more. Since Grasshopper “lives” inside a super solid 3D modelling software you will get there a lot quicker than vvvv, which is more universal and in a sense more powerful for realtime applications. If you want something purely for modelling and to export geometry you will be better of with Grasshopper.
Here is an example from Grasshopper using the Exoskeleton plugin: